A quiz consists of 780 true or false questions. If the student guesses on each question, what is the standarddeviation of the number of correct answers?
A) 13.96424
B) 0
C) 2
D) 19.7484177

Question

Quizplus · Accepted Answer

The standard deviation for a binomial distribution is calculated using the formula √(n*p*(1-p)), where n is the number of trials (780) and p is the probability of success (0.5 for guessing). This results in √(780*0.5*0.5) = √195 = 13.96424.

A Quiz Consists of 780 True or False Questions